Previously, masses have been electromagnetically accelerated to relatively high velocities by devices known as rail guns. In rail gun devices, a single continuing voltage pulse is applied between a pair of parallel guide rails along which the mass is accelerated. The pulse causes a current to flow across a rear surface diameter of an electrically conducting, metal projectile which forms the mass. The projectile is guided and constrained by the rails along which it traverses. Frictional forces between the projectile and the rails materially limit the attainable projectile velocity and frequently result in the effective destruction of the rails or projectile. However, without the rail constraint, the projectile motion is unstable and unpredictable as is the projectile flight.
Accelerating small metal projectiles in strong travelling wave magnetic field devices has been suggested. However, the magnetic field induces considerable eddy currents in the metal projectile, frequently causing overheating of the projectile, which in turn results in melting of the projectile. Hence, if accelerating fields required to achieve high projectile velocity are employed, the projectile has a tendency to be destroyed by its accelerating forces. There have also been suggestions that superconducting projectiles could be accelerated in various magnetic field geometries. However, it is unlikely that such projectiles would remain in the superconducting state if subjected to the magnetic fields required to propel the projectile to a high velocity.
It is, accordingly, an object of the present invention to provide a new and improved method of and apparatus for accelerating a solid mass to very high velocities by electromagnetically derived forces.
Another object of the invention is to provide a new and improved method of and apparatus for accelerating a solid mass to a very high velocity by the use of electromagnetically derived forces that guide the mass, and avoid the need for constraining rails.
Another object of the invention is to provide a new and improved method of and apparatus for accelerating a solid mass along a predetermined path wherein force fields resulting from the electromagnetic source do not tend to have a destructive effect on the mass.
Another object of the present invention is to provide a new and improved electromagnetic method of and apparatus for accelerating a solid mass along a predetermined path at high velocity in such a manner that eddy current overheating of the mass does not occur.
Still another object of the invention is to provide a new and improved electromagnetic method of and apparatus for accelerating a mass stably along a predetermined path wherein the mass is approximately at room temperature or in some cases lower than room temperature but above cyrogenic temperatures as it enters an accelerating field.